“Each expansion of drone use magnifies the concerns of the legal and human rights communities about whether the United States is dangerously pressing the limits of -- or even violating -- international law. Just as worrisome, experts say, is whether the increasing use of drones in such circumstances will slowly erode the force of international law, rendering it ineffective.”

After noting comments from several leading Catholic law professors, Roberts raises what many consider is the central question: must traditional international law change in this new era of non-state terrorism?

“Terrorists don't conform to national boundaries, national allegiances or recognized governments, raising the question of whether a war on terrorism necessarily changes the nature of war itself.”

It’s a question the U.S. and the international community will have to answer, better sooner than later.